Add support for SamRock protocol on integrated L-BTC wallet

Docs: https://plugin-builder.btcpayserver.org/public/plugins/samrock-protocol

It's an easy way to connect your L-BTC wallet (i.e. Bringin) to Btcpayserver. BtcPay generates a paring code --> scan with Bringin app --> Bringin app send wallet descriptor to BTCpayserver and the wallet is added as backend to your store

If Customer pays an btcpay invoice, the sats directly end in the Bringin internal (L-BTC) wallet.

Currently only Aqua Wallet supports it, but any L-BTC wallet should work. You can basically use your self-custodial wallet on your phone as a backend for a Btcpayserver store.